Electronic operations of a suspended particle device

ABSTRACT

A scalable apparatus and a network environment dynamically changes the light transparency of a single SPD device, a small number of SPD devices or thousands of such SPD devices installed in windows in automobiles, aircraft, trains, marine vehicles, residential homes, commercial buildings and skyscrapers. A scalable apparatus and a network environment dynamically changes the light transparency of a single SPD device or thousands of such SPD devices in the presentation of a multi-media special effects display. Textual messages, graphical images and simulated motion effects are driven. Such scalable apparatus being capable of driving and using several operational parameters of SPD&#39;s such as frequency range, AC voltage and temperature so as to provide fine control of SPD characteristics such as switching speed and power consumption.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/855,782 filed Aug. 13, 2010, which is a continuation of U.S.application Ser. No. 11/530,310 filed Sep. 8, 2006, which in turn claimsthe benefit of U.S. application Nos. 60/596,198 filed Sep. 8, 2005,60/721,731 filed Sep. 28, 2005, and 60/597,162 filed Nov. 14, 2005, eachof which is incorporated herein by reference for all purposes.

BACKGROUND OF THE INVENTION

Light valves have been in use for more than sixty years for themodulation of light. As used herein, a light valve is defined as a cellformed of two walls that are spaced apart by a small distance, at leastone wall being transparent, the walls having electrodes thereon, usuallyin the form of transparent, electrically conductive coatings. The cellcontains a light-modulating element (sometimes herein referred to as an“activatable material”), which may be either a liquid suspension ofparticles, or a plastic film in which droplets of a liquid suspension ofparticles are distributed.

The liquid suspension (sometimes herein referred to as “a liquid lightvalve suspension” or “a light valve suspension”) comprises small,anisotropically shaped particles suspended in a liquid suspendingmedium. In the absence of an applied electrical field, the particles inthe liquid suspension assume random positions due to Brownian movement,and hence a beam of light passing into the cell is reflected,transmitted or absorbed, depending upon the cell structure, the natureand concentration of the particles, and the energy content of the light.The light valve is thus relatively dark in the OFF state. However, whenan electric field is applied through the liquid light valve suspensionin the light valve, the particles become aligned and for manysuspensions most of the light can pass through the cell. The light valveis thus relatively transparent in the ON state. Light valves of the typedescribed herein are also known as “suspended particle devices” or“SPDs.” More generally, the term suspended particle device, as usedherein, refers to any device in which suspended particles align to allowlight to pass through the device when an electric field is applied.Light valves have been proposed for use in numerous applicationsincluding windows, skylights, and sunroofs, to control the amount oflight passing therethrough or reflected therefrom as the case may be. Asused herein the term “light” generally refers to visible electromagneticradiation, but where applicable, “light” can also comprise other typesof electromagnetic radiation such as, but not limited to, infraredradiation and ultraviolet radiation.

The SPD is laminated between two pieces of glass or plastic to form asandwich which is sometimes called SPD Glass or SPD Plastic, and whichcan be further used to form a glass or plastic window. With such SPDsforming a window, the amount of light passing through the window can befinely controlled based upon the characteristics of the electricitypassing through the SPD. The degree to which something reduces thepassage of electromagnetic radiation is known as opacity. When referringto windows, changes in opacity is often noted as a change in a windowstinting, its light transparency or transparency and each of these termsmay be equally be used to mean the same.

Such SPDs are now being installed into glass so that the amount of lightpassing through the glass can be finely controlled based upon thecharacteristics of the electricity passing through the glass. At leastone method by which such glass and thus its opacity or lighttransparency may be controlled is described by Malvino, in U.S. Pat.Nos. 6,897,997 and 6,804,040 collectively referred to as the Malvinopatents. But a device envisioned by Malvino, while suitable for themanual control of a small number of co-located windows, is not scalablenor does it provide the automated intelligence to actively anddynamically control environments of more than a few windows such as inan automobile, marine vehicle, train or aircraft, to as much as aresidential or commercial building or a skyscraper of such SPD windows.

The Malvino patents provide the basis for driving SPD glass by varyingvoltage at a fixed frequency which will cause the glass to lightentoward clear or to darken so as to block most light passing through it.That device is capable of mapping the non-linear characteristics of SPDinto a linear range of values that could be thought of as setting theglass from say 0 to 100%. The range is broken down into a small discreteset of settings for perhaps 6 different opaqueness levels and 6 specificresistor and capacitor combinations are built into the implementationand are manually selected to set the proper voltage for the associateddegree of tinting. Through that implementation, a linear manual control,such as a slide switch or a rotating dial may be attached to the Malvinocontroller to directly vary the amount of light allowed through theglass at any time.

The Malvino patents review the use of a few fixed frequencies at whichto drive an SPD. As described, driving the device at a lower frequencytends to have a slight lower energy utilization curve with regard to thepower needed to drive the SPD. Frequencies in the range of 15 hertz to60 hertz were discussed. There is a serious potential problem with theaforementioned controller operating the SPD when driven by thesefrequencies. It is possible that the SPD will “sing” and be heard as atone in the B-flat range by being driven by a fixed frequency withinthat range. An SPD controlled window typically consists of SPD-capablematerial in the form of a clear Mylar coated with SPD emulation, placedin between two pieces of glass. The SPD is basically sandwiched and heldin place by glass on both sides. If 50/60 Hertz current travels throughthe sandwiched SPD, in some cases, the Mylar will start to vibrate inresonance with the driving frequency and may be heard by people near thewindow as an annoying hum.

A considerable issue in the wide-scale worldwide deployment of SPDwindows, is on how residential and commercial buildings will be wired upto allow some “central intelligence” to operate the individual windows.Today, there is no concept of running wires to windows from some controlroom in the building. It is not desirable to introduce a new requirementfor building wiring in the introduction of SPD glass around the world,since thousands of installation people would need to learn andunderstand new building wiring requirements. Yet, if any othertechniques are employed to “wire” each window to the “centralintelligence”, it must require little or no training, and be arelatively low cost so as not to make the use of SPD glass prohibitive.

SUMMARY OF THE INVENTION

The invention relates to a wirelessly enabled apparatus and associatedmesh networking software installed in large arrays in order todynamically control the “skin” of residential and commercial buildingsthroughout the day in order to absorb or reflect sunlight in such amanner as to dramatically reduce the energy consumption of suchbuildings. The integration of a mesh network lowers the cost ofdeployment of such control by permitting the individual devices thatcontrol one or more windows, to act as a relay point in moving controlsignals from intelligent control points in a Building Skin ControlSystem to the individual controllers or sets of controllers which willeffect the desired changes. The invention further relates to a SuspendedParticle Device control apparatus and associated network installed inlarge arrays in order to dynamically control the glass windows ofresidential and commercial buildings throughout the day in order toabsorb or reflect sunlight in such a manner as to dramatically reducethe energy consumption of such buildings. The use of a hierarchicaldistribution system over a LAN or WAN reduces the time to transmitcommands from a central intelligence point, the Master Building ControlPoint, to all window controllers in a structure to set individualwindows to a specific level of opaqueness.

The device described herein corrects for the “singing” problem byproviding the option of driving the SPD at a variable frequency in thelow frequency range rather than a single fixed frequency. Optionally, inlieu of using a continuously variable SPD driving frequency, theController may randomly drop or phase shift several cycles per second.The change/shift is not enough to be visibly noticeable but it wouldeliminate the “ringing effect”. As will be seen below, the systemaccording to the invention scales from the single-window environment toa building with a size beyond that of the currently largest in theworld, Taipei 101 in the Xin-Yi district of Taipei, with over 32,000windows.

This invention provides for a range of SPD control far beyond thatpreviously in existence. The “Scalable Controller” a.k.a. “SC” of thisinvention adds intelligence that greatly expands the capabilities ofprior controllers. As in prior implementations, one to several pieces ofglass may be controlled by a single controller, where several is arelatively small number such as 8 and each piece of glass is hardwiredto the controller. The Scalable controller further supports a setupphase whereby the user may configure the relationship between manualexternal control or several individual manual controls and whichwindow/windows are to be controlled from that manual setting. In asetting of four windows under the Scalable Controller, where the windowsare referred to as A, B, C and D, a user may configure the SC so thatwindows AB are controlled as a single window and CD as another, or ABCis controlled as a single window and D as another, or ABCD is controlledas a single window or, A B C D are controlled as 4 separate windows.

This system coordinates the settings of each of the windows in abuilding in an intelligent manner from a central intelligence pointknown of the Master Building Control Point. It will make intelligentdecisions based on many factors including real time events, as to theproper amount of visible light to permit to flow through each window inorder to take best advantage of the solar heating effect.

Enhanced capabilities of the SC over prior inventions provide for fullcontrol of all operational parameters which effect the characteristicsof a SPD. This type of control exists in each SC to optimize SPDperformance by power utilization or switching speed potentially takinginto account external temperature, while controlling the haze andclarity.

The flexibility of the SC and its networking capabilities also supportthe display of textual messages or special light tinting sequences aspart of a multimedia presentation. Such a multimedia display couldchange windows along the facade of an office building in time to thechanges in perhaps Christmas Music during the holiday period. Ascaled-down version of such a system could provide for a moving textualdisplay across small SPD pixels sitting in a box on a desktop. Thesediverse applications reflect the flexibility and importance of thisinvention.

BRIEF DESCRIPTION OF THE DRAWING

The invention will be described with respect to a drawing in severalfigures, of which:

FIG. 1 is a diagram showing an SPD window controller under manualadjustment from a single external device.

FIG. 2 is the controller of FIG. 1 with the addition of a photocell orother photosensor to detect the brightness of sunlight shining on thewindow under control.

FIG. 3 creates the Intelligent Controller from FIG. 2 by introducing amicroprocessor to perform a number of different functions in support ofmore sophisticated controller capabilities as well as Scalable Networkoperations of controllers. In addition to the photocell or otherphotosensor additional inputs from sensors expand the data which theScalable controller may use to make decisions on how to change windowopacity.

FIG. 4 shows the Intelligent Controller with a plurality of manualinputs that are coupled to one or several window panes that are underthe direct control of the controller as set up by the user via a set upprocedure in the control software. A single manual input may control onewindow or, two, three or four at one time as if it were a single pieceof SPD glass. More then one manual input may be used to control the sameset of glass in order to support manual controls that operate fromdifferent points in the same room.

FIG. 5 shows different combinations of four-window panes in thisexample, and how the set up software allows any combination of sets ofindividual panes to be treated as a single pane of glass.

FIG. 6 shows one of the earliest packet switching or mesh networks inwhich data may be sent along alternate paths through intermediate nodesin order to reach a destination point. This is an example of the 4-nodeArpanet in 1969, the precursor to today's Internet. Host computers sentdata to other Host computers in this network and utilized the servicesof the Interface Message Processor (IMP) to move data packets to otherIMPs which were not destination point but would further relay packetstoward the IMP directly connected to the desired destination Host.

FIG. 7 shows a more advanced packet switched meshed network in whichspecific processing applications operate on the same computer that isrunning the packet switching software thereby combining the functions ofHosts and IMPs in the earlier Arpanet systems. Increases inmicroprocessor power allowed these functions to be combined onto asingle platform. This is an example of a Radio Paging Networkapplication utilizing the Data Link Handler (DLH) protocol created bythe Inventor to convert isolated Citywide radio paging (beeper) systems,also known as Paging Terminal Nodes (PTNs), into a nationwide networkcapable of alerting someone wherever they are located in the countryinstead of just a single city. The Arpanet and Internet utilizeformalized routing protocol specifications such as the RoutingInformation Protocol (RIP) to dynamically maintain a list of best routesto a destination at each node. DLH utilizes a proprietary routingprotocol to maintain a list of primary and alternate routes. Theproprietary DLH network was eventually replaced with the Radio PagingIndustry standard Telocator Network Paging Protocol (TNPP) protocolwhich the Inventor helped to create and Chaired the Industry committeeto promote the use of this protocol for more than 11 years. TNPP wasused along with a manufacturer-specific proprietary routing protocol tomaintain the best and alternate paths to each destination node.

FIG. 8 shows a Scalable Controller network consisting of theIntelligence Controller of FIG. 3 integrated with a radio transceiver(XCVR) to send packets of data to other transceiver equipped ScalableController (CTL) nodes. Routing data similar to the Internet RIP,maintains a list at each Controller node of the best next node toreceive data on the path to the destination node. Unlike the wirednetwork of FIGS. 6 and 7, the radio network of FIG. 8 may sometimesproperly receive data addressed to a different node than that whichreceived it. In this case, the received data is ignored/dropped by thenode which is not the next node along the optimal path to thedestination.

FIG. 9 shows an example of a network of FIG. 8 where a Building ControlPoint is connected to one of the nodes of the network. The BCP is a dataprocessing site to determine which portions of a building are to beautomatically set to a specific opacity at any moment of the day ornight. The Data Processing system may optionally be connected to theInternet and to a remote central monitoring service which oversees theoperations of the SPD Building Skin Control System on behalf of manybuilding owners.

FIG. 10 shows an example of a redundant Master Building Control Point(MBCP) consisting of a primary MBCP and a secondary MBCP in the networkto insure that the entire system continues to operate normally even ifthe primary MBCP should fail. If the primary MBCP should fail, thesecondary MBCP will take over its functionality so that the entiresystem continues to operate normally.

FIG. 11 shows how different areas of a building would have differenttypes of Hierarchical Control Points to oversee the operation ofScalable Controllers in certain portions of a building.

FIG. 12 is a Hierarchical mapping of Control Points showing how commandsgenerated at the highest level Control Point are logically distributedto lower level Control Points that distribute the commands to more andmore elements at lower hierarchy levels.

FIG. 13 shows how the Master Building Control Point interfaces with anIntelligent Energy Control System (IECS) via a computer interfaceutilizing the widely used Extensible Markup Language format referred toas XML.

FIG. 14 shows how the path of the Sun across the sky changes how thesunlight falls on the windows of a building throughout the day. The Sunpath changes slightly each day of the year as the Earth rotates aroundthe Sun. For any latitude and longitude on the planet, the path that istraversed is well known.

FIG. 15 shows five controllers each controlling twenty-four panes.

FIG. 16 shows the letter “E” formed by a 5 by 7 pixel array with aborder.

FIG. 17 shows a lighting effect in which each pane differs from itsneighbor by a few percent.

FIG. 18 shows a controller sending a command to a decoder which in turncommunicates commands to windows.

FIG. 19 shows two Scalable Controllers (SCs) consisting of theIntelligent Controller of FIG. 1 integrated with a LAN interface so thatthey can send packets of data to a Master Control Point (MCP) located onthe LAN.

FIG. 20 shows that when LANs has reached its maximum capacity, due tocable length, a Bridge may be introduced in order to add another LANsegment to extend the size of the LAN.

FIG. 21 shows how to further extend the size of a local network when themaximum number of LAN segments and Bridge/Repeaters has been deployed.

FIG. 22 shows the logical connections that form a hierarchy of controlpoints in order to reduce the point to point communication loading onthe MCP to issue commands to all SCs in a building.

FIG. 23 shows how the Master Control Point, which provides the centralcontrol intelligence for all of the individual windows in a structure,can connect to an external Intelligent Energy Control System via acomputer interface using the widely used Extensible Markup Languageformat referred to as XML. The external system can modify its operationsknowing where windows have been changed. The external system may receivesensor input through the MCP and may command the MCP to modify thesetting or some or all windows under its control. The MCP also has theoption of changing the operation of the windows under IECS command ifbetter algorithms have been developed on the IECS and the Externalsystem starts sending the proper control commands.

FIG. 24 shows the major subsections which comprise the ScalableController.

FIG. 25 shows one of the typical three-dimensional tables of data thatis programmed into the controller to operate it. Such table provideinformation on the interaction of three variables that together controlthe operation of SPD based glass.

DETAILED DESCRIPTION OF THE INVENTION

With the incorporation of a Microprocessor into the Scalable Controller,the capabilities and flexibility of the device are expanded dramaticallyfor use both in a standalone environment as well as being a data pointin a sea of such controllers which, under such intelligent control, candynamically modify the skin of an office building to provideunprecedented control over its energy usage. Even in the standaloneenvironment, the SC can be programmed with the intelligence to reduceenergy usage in the room where it is being used. The SC may be put intoan automatic mode instead of being under manual control and can operateas described below.

Although the same functions may be achieved in several ways, in theimplementation described herein, the end user has the ability to set thelatitude, longitude, window orientation from North, and window anglefrom vertical into a suitable data processing program. This programcreates a profile that can be downloaded into the SC which uses thesetup data to determine the location on the earth of the window(s) undercontrol and thereby, for each window, its angle from the sun at any timeof the day. A time/date clock operates in the SC to drive its window(s)based upon the time of day, day of year, and the location on the planet.At 1:00 PM on July 2nd in Manhattan, N.Y., the windows directly facingthe sun would be set to the maximum opaqueness while those angled awayfrom the sun would have reduced opaqueness and those on the oppositeside of the building might be totally clear. As the sun crosses the sky,each window changes according to the built-in profile. Yet at 1:00 PM onJuly 2nd in Sydney Australia, those windows facing the sun will beclear, so that the building's heating system requirements may be reducedby utilizing the sun to heat windows directly facing the sun, whilewindows on the opposite side of the building would be turned dark so asto keep heat trapped in the building. A photocell connected to the SCwill provide external sensor input so as to allow the SC to further finetune the current opaqueness based upon current cloud and weatherconditions. Sidereal information has been well known and calculable forcenturies and may thus be profiled into the SC device itself. Weatherconditions that might block the sun are random real-time events.

Although such Intelligent control permits several windows to operateautonomously, in a larger-scale implementation, it is desirable to putentire segments of building windows under a coordinated set of controls.In relatively large types of environments, rather than using a profileof individual windows, it is possible to perform more real-time dataprocessing and to make more intelligent decisions of the opacity ofevery segment of a building at any point in time. The SC of thisinvention is capable of expanding so as to operate in such a mode.

This system virtually eliminates all building wiring issues to put allSPD windows under a central control. Each Scalable Controller isoutfitted with a low-power, low-data-rate, limited-range, radiotransceiver. These radio transceivers are capable of communicating on apoint-to-point basis to one or more radio transceivers located withinother Scalable Controllers in a 3-dimensional space around eachcontroller. The SC microprocessor is further outfitted with meshnetworking software. Such types of software have been in existence invarious incarnations for a long period of time. The radio transceiverssend specially formatted packets of data back and forth between eachother. Some packets contain data which is used to operate the meshnetwork itself while other packets contain sensor data or window controlinformation. Routing control packets are one type of mesh control packetwhich is sent. Each SC can be thought of as a “node” in the meshnetwork. The routing information is used to leave information at eachindividual node to indicate an available “route” to move data from awindow controller to another intermediate window controller along a pathto a “Hierarchical Control Point (HCP)” or from an HCP throughintermediate window controllers on its way to a specific individualwindow controller. An HCP is the location of a special data processingnode, as opposed to a window controller node, which is capable ofcoordinating the changing of the opaqueness of windows for some segmentof a building. There may be several Office Control Points (OCP), SectionControl Points (SCP), Region Control Points (RCP), Floor Control Points(FCP), Multi-floor Control Points (MCP) and a single Building ControlPoint (BCP) located in typical building environment. A single ControlPoint might exist in a small implementation while all types of ControlPoints may exist in a very large-scale implementation. The use ofadditional Control Points reduces communication overhead in the meshnetwork and decreases the time delay between the time a windowopaqueness modification command is sent and when it is acted upon atindividual windows. In this instantiation of the invention, any windowSC can become a Control Point via a command sent from the BuildingControl Point. Although a Building Control Point is an Intelligent DataProcessing System, the lower hierarchical control points have arelatively small set of fixed commands and operations which can easilybe handled at the Microprocessor at any window SC. In the largest-scaleimplementation of the Scalable Controller Network, the BCP can informthe Multi-Floor Control Points (MCP) to change the settings of eachwindow on all floors; the MCP will distribute this request to each ofthe FCP's; the FCP's will distribute the request to the RCP's; the RCP'swill send the command to SCP's; and the SCP's will forward the commandsto OCP's which will command each window controller in an office toexecute the required change. Because of the expansion to multiple nodesat each level of the hierarchy, commands may be simultaneously sentwithin different non-overlapping areas of the network where they maypass through intermediate nodes with no or little queuing delay, thushaving the request executed throughout the building in a seeminglysimultaneous fashion.

Typically, a window controller is not in direct radio communication withthe location in the building where a HCP might be located. But everywindow controller will typically be within radio communication ofseveral other window controllers. The mesh networking software permits adata packet to be sent from a source node to any neighboring node thatis along a path which eventually leads to the destination node, througha series of hops through intermediate nodes. Because of the multiplepaths that exist between nodes, data can typically be routed aroundareas of the network that might be temporarily undergoing radiointerference. Data retransmission and acknowledgments duringpoint-to-point communications insure that data is not dropped by onenode until the next node in the network has accepted the data beingsent. If such acknowledgment is not received, a node may send its dataonto an alternate path to the destination. If a segment of the radionetwork should become isolated, a packet hop count insures that packetswhich will never reach their ultimate destination are eliminated fromthe network. End-to-end acknowledgments let the source and destinationnodes recognize when data must be retransmitted in its entirety becauseit may have been dropped due to a particular radio failure creatingisolated subnetworks. Reporting processes built into the BuildingController monitor the nodes in the network, gather interconnectivitydata, and take into account the window controller addresses to assistthe installer in insuring that all nodes are capable of communicatingwith the Hierarchical Control Points. Where it might be found that someportion of the overall network is isolated from another portion, specialnodes may be installed in a geographical area between existing segmentsof the network, in order to provide a bridging point for data to movefrom one network segment toward the other. There should typically be atleast two nodes to bridge isolated segments together. The bridges arenothing more than window Scalable Controllers that are not connected toany SPD window.

The Scalable Controllers may be equipped with various types of sensorsthat may be used in more finely controlling the energy usage in abuilding. A photocell may be placed onto each SPD glass and connected toits SC. The Building Control Point “BCP” may command all the SCs toperiodically send sensor data to the BCP or the BCP may periodicallypoll each of the SCs to read photocell and other sensor data. Through aninitial system configuration procedure at the BCP, it is made aware ofthe configuration of the building, the compass direction in whichwindows face, the latitude and longitude of the building, the angle atwhich each window is from the vertical, and the location of unique nodeand window addresses. Input from photocells throughout the buildingallow the BCP to utilize voting techniques to determine the best areasof the building in which to increase or decrease opaqueness in order toreduce the overall building energy requirements for heating and airconditioning. If a readable compass and glass angle detector isinstalled at each SC, the process of modeling the building to establishmore precise control of each window, is simplified, by directlyproviding this configuration information.

The BCP allows the system operator to establish special overrides forportions of the building at certain times of the day and days of theyear. This might be utilized to specify a region of the buildingundergoing glare from reflections from other buildings or naturalfeatures in the area. The override features would allow a normally clearwindow to perhaps to be darkened for some period to eliminate the glareonto that portion of the building. So some regions of a building mightbe under automatic control while other segments of the building may beunder special override conditions at the time. A complex combination ofeach control may be in effect at one time.

Many “Green” buildings already incorporate an Intelligent Energy ControlSystem such as the Honeywell Enterprise Buildings Integrator (EBI).These types of systems operate/monitor/control the building HVAC system,circulation of fresh air, elimination of building odors, control ofelectric usage, and reduction of energy requirements to unoccupiedareas. These top-of-the-line systems also incorporate building security,monitoring and access control, asset tracking, fire and smoke detectionand even control fire doors and public announcement systems. Thisinvention extends the capabilities of these sophisticated systems in amanner that was never possible before. These system may now effectivelycontrol the skin of the building dynamically during the day, optimizingthe use of the sun along with the movement of heat and air conditioningaround the building. The combination of both systems provides a level ofefficiency of an even higher level than that capable of standalonewindows or BCP controlled windows, since it directly controls multiplesubsystems in a building in a coordinated fashion.

In this instantiation of the invention, the BCP will provide aninterface to an external system to provide additional sensor data to theexternal system and to allow the external system to request adjustmentsto light levels around the building in a high-level form. One of thepreferred high-level forms in which an external system will representsensor data and requests to adjust light levels to the BCP and the BCPwill represent responses to such data and requests through thisinterface is known as XML. XML is an abbreviation for Extensible MarkupLanguage and is a widely used open standard for organizing andexchanging structured documents and data between two computers. Acomputer to computer link over which data is transferred in the XMLformat. is often referred to as an XML link or an XML interface. The BCPtakes requests from the XML link, interprets them and executes them bysending the proper commands through the hierarchical network to effectthe changes requested by the external Intelligent Energy Control System(IECS). When operating in this mode, the automated controls of the BCPare bypassed. A periodic “heartbeat” transfer of XML command/responsesover the BCP/IECS link insures that the two systems remain in sync andthat they coordinate operations. In the event the heartbeat is lost, theBCP can fall back to its automated mode and operate the buildingindependently until the IECS system comes back on-line.

This invention utilizes low-cost, low-power, limited-range RadioTransceivers co-located with each window controller device, to form alarge scale wireless network between all of the windows in a residentialor commercial building. Windows are typically within 10 meters of eachother within buildings, so limited range transceivers are perfectlysuited for this environment. The microprocessor-driven software withineach controller operates the local application functions of thecontroller while at the same time executing radio packet switching typesoftware used to send messages from source nodes to destination nodes ina building, even though the source and destination node are not indirect communication with each other because of their distance from eachother. The data which are to be moved from the source to the destinationare sent to a transceiver which is reachable from the source node, andtoward another radio transceiver that is reachable along a path whichwill eventually get the packetized data to the desired destination.

The technique of moving messages from source computers to destinationcomputers through intermediate points in a multiply-connected array ofcomputers was originally referred to as Packet Switching and was firstcharacterized in the Arpanet, the precursor to the Internet in 1969.FIG. 6, which represents the Arpanet's 4-node network operational inDecember 1969, could potentially send a packet of data from Host 161 toHost 163, by handing the data packet to Interface Message Processor(IMP) 61, which might forward it to IMP 62, and to IMP 63 where it ishanded to destination Host 163. If IMP 62 finds that the link to IMP 63is not functioning for some period of time, the same data from Host 161to 163 could be handed over to IMP 64 to forward the data to IMP 63instead of using the failed direct link. The concept in apacket-switched network is to locate alternate paths to get the packetto the ultimate destination point even if some individual communicationpaths are out of service. Some packet networks utilize fixed routingtables to define alternate data paths in the event of link failures andhave algorithms to determine when primary or alternate paths are to beutilized. Other packet networks have dynamically updated routinginformation that is periodically updated between adjacent nodes in orderto continually maintain a list of the best route to any ultimatedestination in the network.

With improvements in hardware and software, the separation of a Host(applications processor) and a packet switching network of nodes (theInterface Message Processors—IMP's) was no longer necessary. The 1980ITT-DTS Faxpak facsimile Store-and-Forward packet switching systemintegrated an application which provided compatibility between differentspeed fax machines of the time, with a message passing network whichallowed messages to always be delivered locally instead of via what (inthose days) were more expensive calls over long-distance lines. The WideArea Paging network in FIG. 7 ran an application that permitted any nodein the network to accept a paging message (phone number) specifiedthrough a dial-in telephone call, a text message received from anoperator, or a message received from a remote node, to a paging messagethat would be encoded and transmitted at a destination node. The packetswitching software that operated at the same nodes, directed pagingapplication packets to be dropped off at the proper destination node ornodes to page a person in multiple cities.

Packet networks typically operated with dedicated communication circuitsbetween nodes in different cities. More recently, the same multi-pathpacket switching technique has been deployed into networks of radiotransceivers, utilizing radio links in lieu of wired links between pairsof nodes. These radio packet switching systems have become known as meshnetworks. Unlike the 2-D wired communication circuits as in FIG. 7, theradio devices in a mesh network permit point-to-point communicationswithin a 3-D region of each node. In an office environment, where eachwindow may represent a node, windows within a few feet left or right ofa particular window can be thought of as potential intermediate nodes,as well as windows that are potentially a few floors above or a fewfloors below a particular window.

In this instantiation, a header packet in each transmission packetspecifies the source node address, destination node address and theaddress of the next hopping point along the path to the destination.This data is transmitted in three dimensions when it is time for thisScalable Controller to transmit information to another point in thenetwork. Many receivers will detect interference in the data theyreceive, and will ignore the received data. Several other receivers mayreceive the packet but with transmission errors. Only the node to whichthe correctly received packet is addressed will keep the packet, analyzeit and will decide if the data item is to be forward toward anotherintermediate node to the final destination or if the packet is to behandled by the application software at this node.

To allow multiple commands to be outstanding and be executed atdifferent points in the network simultaneously, a logical hierarchicalstructure is introduced into the network. Certain network nodes aredesignated as Hierarchical Control Points (HCP) that only forward datatoward lower level Hierarchical Control Points. Ultimately, the lowestlevel HCP logically forwards data only to a subset of all ScalableControllers in the network. This logical configuration allows a singlecommand to be branched out in multiple commands and each of thosecommands to further expand to even more multiple commands, therebycontrolling the maximum number of nodes with the minimal number ofcontrol messages at the highest level. So a command to make all windowsclear in a segment of a building would be initiated at the highest levelnode and be handed down to lower levels nodes that understood where thiscommand needs to be sent in order to effect the desired windows in thebuilding.

On the other hand, sensor data that was considered as an urgent dataitem to which to reach, captured at the individual Scalable Controllers,would be directed to higher and then higher levels of HCPs until thedata item reaches the highest level HCP.

Turning to FIG. 1, we see an SPD window controller 2 under manualadjustment from a single external device 1. It controls a window 5.

FIG. 2 shows the controller of FIG. 1 with the addition of a photocell10 to detect the brightness of sunlight shining on the window 5 undercontrol.

FIG. 3 creates the Intelligent Controller from FIG. 2 by introducing amicroprocessor 3 to perform a number of different functions in supportof more sophisticated controller capabilities as well as ScalableNetwork operations of controllers. In addition to supporting thephotocell 6 or other photosensor as the non-Intelligent controller ofFIG. 2, additional inputs from sensors 8 expand the data which theScalable controller may use to make decisions on how to change windowopacity.

FIG. 4 shows the Intelligent Controller with a plurality of manualinputs 1 that are coupled to one or several window panes 51-54 that areunder the direct control of the controller as set up by the user via aset up procedure in the control software. A single manual input maycontrol one window or two, three or four at one time as if it were asingle piece of SPD glass. More than one manual input may be used tocontrol the same set of glass in order to support manual controls thatoperate from different points in the same room.

FIG. 5 shows different combinations of four-window panes in thisexample, and how the set up software allows any combination of sets ofindividual panes to be treated as a single pane of glass. In a settingof four windows under the Scalable Controller, where the windows arereferred to as A, B, C and D, a user may configure the SC so thatwindows AC are controlled as a single window and BD as another, or BCDis controlled as a single window and A as another, or ABCD is controlledas a single window or, A, B, C, D, are controlled as four separatewindows.

FIG. 6 shows one of the earliest packet switching or mesh networks inwhich data may be sent along alternate paths through intermediate nodesin order to reach a destination point. This is an example of the 4-nodeArpanet in 1969, the precursor to today's Internet. Host computers sentdata to other Host computers in this network and utilized the servicesof the Interface Message Processor (IMP) 61 to move data packets toother IMPs 62, 64 which were not destination points but would furtherrelay packets toward the particular IMP 63 directly connected to thedesired destination Host 163.

FIG. 7 shows a more advanced packet switched meshed network in whichspecific processing applications operate on the same computer that isrunning the packet switching software thereby combining the functions ofHosts and IMPs in the earlier Arpanet systems. Increases inmicroprocessor power allowed these functions to be combined onto asingle platform. This is an example of a Radio Paging Networkapplication utilizing the Data Link Handler (DLH) protocol created bythe Inventor to convert isolated Citywide radio paging (beeper) systems,also known as Paging Terminal Nodes (PTNs), into a nationwide networkcapable of alerting someone wherever they are located in the countryinstead of just a single city. The Arpanet and Internet utilizeformalized routing protocol specifications such as RIP to dynamicallymaintain a list of best routes to a destination at each node. DLHutilizes a proprietary routing protocol to maintain a list of primaryand alternate routes. The proprietary DLH network was eventuallyreplaced with the Radio Paging Industry standard TNPP protocol which theInventor helped to create and Chaired the Industry committee to promotethe use of this protocol for more than 11 years. TNPP was used alongwith a manufacturer-specific proprietary routing protocol to maintainthe best and alternate paths to each destination node. A paging messageoriginating at Paging Terminal Node (PTN) B 72 might be passed to otherPTNs 73, 74 until reaching a PTN 71 which is in turn coupled withantennas which pass digital information in RF form to a pocket pagingreceiver 171.

FIG. 8 shows a Scalable Controller network consisting of the IntelligentController of FIG. 3 integrated with a radio transceiver (XCVR) to sendpackets of data to other transceiver equipped Scalable Controller (CTL)nodes. Routing data similar to the Internet RIP, maintains a list ateach Controller node of the best next node to receive data on the pathto the destination node. Unlike the wired network of FIGS. 6 and 7, theradio network of FIG. 8 may sometimes properly receive data addressed toa different node than that which received it. In this case, the receiveddata is ignored/dropped by the node which is not the next node along theoptimal path to the destination. Each controller 81, 82, 83, 84 has acontroller, a microprocessor, and a radio transceiver.

FIG. 9 shows an example of a network of FIG. 8 where a Master BuildingControl Point (MBCP) 90 is connected to one of the nodes of the network.The MBCP 90 is a data processing site to determine which portions of abuilding are to be automatically set to a specific opacity at any momentof the day or night. The Data Processing system may optionally beconnected to the Internet 91 and to a remote central monitoring service92 which oversees the operations of the SPD Building Skin Control Systemon behalf of many building owners.

FIG. 10 shows an example of a redundant Master Building Control Point(MBCP) consisting of a primary MBCP and a secondary MBCP in the networkto insure that the entire system continues to operate normally even ifthe primary MBCP should fail. One MBCP (shown as a data processor) isconnected to node 81 and a second MBCP (also shown as a data processor)is connected to a node 87. If the primary MBCP should fail, thesecondary MBCP will take over its functionality so that the entiresystem continues normal operations.

FIG. 11 shows how different areas of a building would have differenttypes of Hierarchical Control Points (HCPs) to oversee the operation ofScalable Controllers in certain portions of a building.

FIG. 12 is a Hierarchical mapping of Control Points showing how commandsgenerated at the highest level Control Point are logically distributedto lower level Control Points that distribute the commands to more andmore elements at lower hierarchy levels. There may be several OfficeControl Points (OCP), Section Control Points (SCP), Region ControlPoints (RCP), Floor Control Points (FCP), Multi-floor Control Points(MCP) and a single Building Control Point (BCP) located in typicalbuilding environment. A single Control Point might exist in a smallimplementation while all types of Control Points may exist in a verylarge-scale implementation. The use of additional Control Points reducescommunication overhead in the mesh network and decreases the time delaybetween the time a window opaqueness modification command is sent andwhen it is acted upon at individual windows. In this instantiation ofthe invention, any window SC can become a Control Point via a commandsent from the Master Building Control Point. Although a Master BuildingControl Point is an Intelligent Data Processing System, the lowerhierarchical control points have a relatively small set of fixedcommands and operations which can easily be handled at theMicroprocessor at any window SC. In an intermediate size implementationof the Scalable Controller Network, the MBCP can inform the FCPs 96, 99;the FCPs will distribute the request to the RCPs 97, 100, 101, 102; theRCPs will send the command to OCPs which will command each windowcontroller in an office (not shown for clarity) to execute the requiredchange. Because of the expansion to multiple nodes at each level of thehierarchy, commands may be simultaneously sent within differentnon-overlapping areas of the network where they may pass throughintermediate nodes with no or little queuing delay, thus having therequest executed throughout the building in a seemingly simultaneousfashion.

FIG. 22 shows the logical connections that form a hierarchy of controlpoints in order to reduce the point-to-point communication loading onthe Multi-Floor Control Point MCP to issue commands to all SCs in abuilding. In the example shown, the MCP sends commands to two FloorControl Points (FCP) that are optimally placed on separate LANs.Simultaneously, each FCP can relay the command to Section Control Points(SCP) that in turn may transmit the commands to Office Control Points(OCP). Each OCP may simultaneously relay the commands it has received tothe one or more SCs for which it is responsible. Ultimately all of theSCs will have received the required commands, but the hierarchicalstructure reduces the total number of data transmissions across theentire network to reach each SC from the MCP.

FIG. 13 shows how the Master Building Control Point 110 interfaces withan Intelligent Energy Control System (IECS) 111 via an XML interface112. FIG. 23 shows in more detail how the Master Building Control Point204, which provides the central control intelligence for all of theindividual windows in a structure, can connect to an externalIntelligent Energy Control System 210 via an XML link 209, so that theexternal system may receive sensor input through the MBCP and maycommand the MBCP to modify the setting or some or all windows under itscontrol.

FIG. 14 shows how the path of the Sun across the sky changes how thesunlight falls on the windows of a building throughout the day. The Sunpath changes slightly each day of the year as the Earth rotates aroundthe Sun. For any latitude and longitude on the planet, the path that istraversed is well known.

Another embodiment of the invention transforms an array of windows intoa part of a multi-media display. Office buildings are often decorated ina manner as to enhance the appearance of the city in which it islocated. In Houston, for example, many of the large buildings areoutlined in rows of small lights on the perimeter of each building so asto form an outline of the cities skyline each evening. During holidays,many buildings will turn specific lights on and off in the building lateat night when the building is primarily empty so as to display somepattern associated with the holiday. For example, during Christmas, across may appear in the windows of a large building. Or diamond shapepatterns may be displayed at different floor levels of a building and atadjacent buildings as part of the winter season.

This embodiment extends the MBCP functions so that it may direct SPDwindows to be part of a video presentation. The controllers areunaffected when adding this capability because they already have theability to change any pane of glass under their control to any settingfrom clear to dark or any setting in between under manual or underautomated control from the MBCP. So a special,non-energy-efficiency-related application may exist in the MBCP tooperate the windows in a special manner as desired by the buildingoperator.

Textual Messaging Mode

There are two modes of operation, although they may both operatesimultaneously. The first mode is to use SPD windows to form a textualdisplay of messages. In its simplest application each pane of SPD glassrepresents a single pixel of information. The size of the window paneand the matrix size making up a letter defines how far away the usermust be from the window to be able to clearly read the letters formed.In some cases a square box of 4 or 9 (2.times.2 or 3.times.3) windowsmay be controlled as one in order to increase the size of an individualpixel. Each controller receives a command from the MBCP to set its pixelto on or off or at some degree of shading. Using a set of 48 windows, a6.times.8 pixel array may form any letter or punctuation and include aone-pixel border around each letter.

The MBCP may operate in another mode where the message(s) to bedisplayed is given to it via an external system rather than from localconsoles on the MBCP. The MBCP will support several interfaces formessage entry. This includes an XML type command set between the MBCPand an external system. The command set may operate over a LANconnection, serial port, infrared port or other physical method. TheMBCP may be programmed with a sequence of letters/words/messages todisplay, with timing information, and with a starting pixel location.Changing the window/pixel settings at the specified rate will providethe sensation that the text message is scrolling across the windows.This is done, for example, by removing one vertical column of pixel dataon the left side of the display by shifting the setting of one window tothe right over to the one window on the left. The column of pixels atthe right-most window is for the next letter to be displayed. Thisprovides a smooth scrolling right to left. In a similar manner theletters may also be scrolled left to right for languages written in theopposite direction. The starting location of each row of text may bespecified so that messages may start at any floor of windows or severalfloors at the same time.

Logic in the MBCP will also provide for other textual display featurestaking advantage of the capabilities of SPD Glass. For example, lettersmay appear upside down and be changed right side up. They could perhapsbe rotated vertically along any of the rows that make up each letter.The pixels can start at clear and the letters can be formed by varyingthe darkness of each pixel individually or from top to bottom or bottomto top for some interesting special effects. Words can be brought intodisplay in the same manner. Darkening columns of pixels left to rightand right to left meeting in the middle of a sentence or starting in thecenter and radiating out to the left and right. Or different startingcolumns may be selected and the pixels may radiate out in one directionor both as the letters darken. There is no limit as to the combinationsthat can be made to make the generation of the display more interestingthan just displaying a letter at a time at a given intensity. Of courseany of these special display methods will be available over the XMLinterface so external devices may drive arrays of SPD Glass.

Although this example reviews the use of SPD Glass on an office buildingas a means of displaying messages, this may be scaled down to smallerapplications, depending upon the size of each pane of glass or pixel.For example, messages could be scrolled across an atrium of SPD glassjust above the heads of people standing under it. Or, if very smallpanes of glass are used, small moving displays of SPD glass could becreated.

Video Mode

The SPD windows on a structure may also be looked at as a sea of pixelseach capable of being set to any shading level from 0% to 100%, the endsof the range being thought of as Off and On. There is an endlesscombination of different light level settings across each pixel in alarge array, to provide many random and well-structured visual effectsthat would entertain people viewing such a display. A large number ofpreprogrammed sets of sequences may be defined and stored in the MBCP.Each sequence may provide some special effect seen across the glass.Sequences may be defined such as:

Flash from all dark to all light

Start from all dark and lighten to clear slowly

from left to right

right to left

top to bottom

bottom to top

center to edge in a increasing squares manner

edge to center

Checkerboard pattern

And many others

The MBCP will support many means of initiating a sequence and theability to store away ‘scripts’ of preprogrammed sets of sequences. TheMBCP will be able to be driven via the serial port or LAN connection ofa PC. It can also support an external device that is actually an arrayof buttons and switches, where the combination of a switch setting andpressing a button initiates a pre-programmed sequence. In this way anoperator may “play” sequences in time to external music, just as a laserlight show operator uses a similar type panel to initiate pre-programmedlighting effects that are in tune with the music playing. An elaboratearray of new sequences may be established off-line and sent to the MBCPfrom an external system at any time. Some of these external sequencesmay be later stored in the MBCP and called up by reference number ratherthan having to repeatedly download the sequence from an external device.For further integration in a multi-media environment, when the windowarray is set to full dark, video projectors could potentially beutilized to display moving images across the SPD glass. This sequencewould be requested when external video projectors are commanded to startdisplaying video data.

The array of pixels associated with one instantaneous state of asequence, is set to specific levels via the sending of wireless commandsto each of the necessary controllers to set its associated pixels to theproper setting. The wireless command may be received directly from theradio interface at the MBCP or via any intermediatenode(s)/controller(s) in the array (mesh packet network) when thecontroller of a particular pixel is not in direct communication with theMBCP.

The ability of the MBCP to provide visual special effects across windowarrays is further enhanced through a set of special interfaces that aresupported by the MBCP. The MBCP can be made to appear as a controllablelighting system to lighting industry standard DMX based IntelligentControl System. These systems already have support for creating andsaving scripts of special effects in support of multi-media lightingshows.

X.10 Control of SPD Windows

The controllers of the invention may operate over a wireless network insupport of automatic remote control in a large building environment. Butin smaller environments, such as a residential project having perhaps 16windows, the wireless control solution may be overly expensive in somesituations. In order to address this situation, there is anothervariation of the scalable controller. Instead of integrating thecontroller with a radio transmitter and receiver as described above,this invention provides an interface to the above controller which iscapable of receiving X.10 control signals over a 110 VAC/220 VAC powerline. A United States patent that is now expired covered the X.10communication protocol. Yet, because of how long it has been inexistence, the number of compatible products that exist, the easyavailability of X.10 controllers that send control signals over thepower line, and their low cost, an X.10 compatible interface isdesirable. FIG. 18 shows a controller 181 transmitting X.10 signals,sending a command to an X.10 decoder 182 which in turn communicatescommands to windows 183

The X.10 interface option will be placed onto the controller circuitcard that is operating one or more panes of glass. Each controller willoperate via a direct power connection to the 110 VAC/220 VAC power line.Up to 256 windows may be controlled in this environment. Each windowcontroller will be assigned an X.10 Letter (Home/Network ID) and NumberCode (Device ID). When the window controller sees its address on thepowerline bus, it will then look for a command signal such as ON, OFF,DIM UP, DIM DOWN. An ON signal will be executed at the controller as asignal to set the window to full Dark. An OFF signal will be interpretedas setting the window to full Clear. The controller maintains thecurrent setting of the window under its control. A DIM UP command willslowly increase the darkness of a window from 0% toward 100% and a DIMDOWN command will slowly decrease the darkness making the windowclearer. Any X.10 device capable of sending these four signals to any ofthe 256 possible X.10 addresses will now be capable of controlling anySPD window. X.10 controllers currently exist to send these four signalsunder manual control or to program a computer to send commands atparticular times of the day. This will provide a very simple means oflocal control of a small number of SPDs. A similar interface will existfor support of several wireless replacements to X.10 devices, Z-Wave,Insteon, and 802.11.15 ZigBee.

FIG. 15 shows 5 controllers each controlling 24 window/panes. Thesewindow panes may physically be aligned so that A and B are next to eachother and E and D are directly below them. This would form an 8.times.12pixel array. Commands from the MBCP will be sent via its localtransmitter, M, into the wireless mesh network. Because of the meshnetworking aspects of the controller network, if the MBCS is capable ofcommunicating directly with controller D but finds it cannot directlycommunicate with controller B, it may route command data through nodecontroller C to command B to set its pixels. To control the settings atnode A, the command may for example go via the path M, D, E. A or M, D,B, A or M, C. B, A.

FIG. 16 shows show the letter “E” formed in a 5 by 7 pixel array ofdarkened windows, with a border at the left and top having a width of asingle window/pixel.

FIG. 17 shows a lighting effect in which each pane differs from itsneighbor by a few percent.

It will be appreciated that this invention provides for a range of SPDcontrol far beyond that previously in existence. The “ScalableController” a.k.a. “SC” of this invention adds intelligence that greatlyexpands the capabilities of prior controllers. As in priorimplementations, one to several pieces of glass may be controlled by asingle controller, where several is a relatively small number such aseight and each piece of glass is hardwired to the controller. TheScalable controller further supports a set up phase whereby the user mayconfigure the relationship between manual external control or severalindividual manual controls and which window/windows are to be controlledfrom that manual setting. In a setting of four windows under theScalable Controller, where the windows are referred to as A, B, C and D,a user may configure the SC so that windows AB is controlled as a singlewindow and CD as another, or ABC is controlled as a single window and Das another, or ABCD is controlled as a single window or, ABCD arecontrolled as 4 separate windows, as mentioned above in connection withFIG. 5.

Although such intelligent control permits several windows to operateautonomously, in a larger scale implementation, it is desirable to putentire segments of building windows under a coordinated set of controls.In relatively large types of environments, rather than using a profileof individual windows, it is possible to perform real-time dataprocessing and make more intelligent decisions of the opacity of everysegment of a building at any point in time. The SC of this invention iscapable of expanding so as to operate in such a mode.

When the SC is in manual mode, it utilizes inputs from the room occupantto control the precise setting of the opaqueness of the SPD glass orplastic it is controlling. There is a range of different manual inputdevices that might be used. Switches, rheostat-like devices, orcapacitance-type devices that have no moving parts but can sense thetouch of a finger, for example, my all be utilized. But the SCs may alsoreceive commands sent to it via a Local Area Network to which the isconnected. The SC allows for the plug in of an LAN card so that it mayreceive commands from elsewhere in the network to control functions tobe performed. Multiple LANs may be connected via Repeater/Bridges toincrease the size of the physical area of building windows that is beingcovered. When the maximum length LAN has been reached, a router can bedeployed to connect independent LANs to each other in the creation of awide area network capable of reaching every SC in the building. Thepurpose of this wide area network is so that each SC may receivecommands that are initiated from a central intelligence point, theMaster Building Control Point (MBCP), where a data processing system ismaking decisions as to the optimal setting of each window. The MBCP iscapable of taking in data from sensors that are collocated with SCs bypolling for their data, and from other inputs that may be read throughthe network it is connected to, utilize latitude and longitudeinformation, time of day, day of year, and other facts in order to makedecisions how to optimally set the current opacity levels across thebuilding. The MBCP may then send commands through the network to eachindividual window to select the optimal setting.

The Scalable Controllers may be equipped with various types of sensorsthat may be used in more finely controlling the energy usage in abuilding. A photocell may be placed onto each SPD glass and connected toits SC (see FIGS. 2 and 3). The Master Building Control Point “MBCP” maycommand all the SCs to periodically send sensor data to the MBCP or theMBCP may periodically poll each of the SCs to read photocell and othersensor data. Through an initial system configuration procedure at theMBCP, it is made aware of the configuration of the building, the compassdirection in which windows face, the latitude and longitude of thebuilding, the angle at which each window is from vertical, and thelocation of unique node and window addresses. Input from photocellsthroughout the building allow the MBCP to utilize voting techniques todetermine the best areas of the building in which to increase ordecrease opaqueness in order to reduce the overall building energyrequirements for heating and air conditioning. If a readable compass andglass angle detector is installed at key SCs, the process of modelingthe building to establish more precise control of each window, issimplified, by directly providing this configuration information.

In order to reduce the overall load on the backbone of the LANs and toallow commands to be executed truly simultaneously across the network, ahierarchy of Intelligent Control Points may be created. The controlpoints could be nothing more than individual SCs that are commanded bythe MBCP to act as relay stations on behalf of the MBCP. At the highestlevel of the hierarchy, the Master Building Control Point exists thatmakes intelligent decisions as to the current settings of opaqueness atall points in a building of SPD glass. Depending upon the size of theimplementation, there are several levels of hierarchy. The MasterControl Point sends opaqueness modification commands to one or more ofthe Hierarchical Control Points that in turn communicate with severallower level Hierarchical Control Points and eventually to each of theindividual SCs for which it is responsible. Such a multi-leveldistribution of control reduces the volume of data packets traversingthe LAN on which the Master Control Point exists and hands off thecommand distribution to each of the local LANs thus reducing the load onthe Master and on the backbone network. It also allows for commands tobe executed more quickly than if each had to be sent directly from theMaster Control Point, since each Hierarchical Control Point isperforming the distribution of commands for the Master on each of itslocal LANs. Therefore commands are sent simultaneously across multipleLANs instead of serially. This allows a very large number of SuspendedParticle Devices to be changed more quickly and simultaneously.

In this instantiation of the invention, the MBCP will provide an XMLinterface (as shown in FIG. 13) to an external system to provide windowtinting information and additional sensor data to the external systemand to allow the external system to request adjustments to tintinglevels around the building or adjust room lighting under its control.The MBCP takes requests from the XML link, interprets them and executesthem by sending the proper commands through the Hierarchical network toeffect the changes requested by the external Intelligent Energy ControlSystem (IECS). When operating in this mode, the automated controls ofthe MBCP can be optionally bypassed, rather than using the derivedinformation to command all windows to set in an optimal way. Instead,the commands are generated based upon the XML messages that are receivedfrom the IECS. A periodic “Heartbeat” transfer of XML command/responsesover the MBCP/IECS link, insures that the two systems remain in sync andcoordinating operations. In the event the heartbeat is lost, the MBCPcan fall back to its automated mode and operate the buildingindependently until the IECS system comes back online Optionally theMBCP can remain in direct control of window tinting providing the IECSwith data to help augment its operations.

FIG. 19 shows two Scalable Controllers (SCs) 191, 192 consisting of theIntelligent Controller of FIG. 1 integrated with a LAN interface 194 sothat they can send packets of data by means of a LAN 193 to a MasterControl Point (MBCP) 192 located on the LAN.

FIG. 20 shows that when each of several LANs 201 has reached its maximumcapacity, due to cable length of in this example, a Bridge 202 may beintroduced in order to add another LAN segment to extend the size of theLAN. This would be the first method used in a structure to be employedto connect more controllers to a Master Building Control Point 204 whichis controlling the settings of all of the SCs. This figure also depictsa Hub 205 which provides direct connectivity to individual SCs 206rather than multiple SCs hanging off a shared wire. The connectionbetween the Hub 205 and the individual SCs 206 may be wired or could bewireless. Using wireless LANs reduces the amount of building wiring thatmust be done to connect every Scalable Controller to the network thatwill provide connectivity to the Master Control Point 204 containing thebuilding control logic.

FIG. 21 shows how to further extend the size of a local network when themaximum number of LAN segments and Bridge/Repeaters 202 has beendeployed. A Router component 207 is added which allows new andindependent LAN segments to be connected to the Router 207. The Router207 recognizes when data has been directed to a LAN address that is on adifferent LAN, and it then takes that data from the receiving LAN andresends it over the correct LAN where the destination address islocated. Mapping tables tell the Router 207 what ranges of addresseseach LAN handles. SCs located all over a large building are connected tothe closest LAN in order to receive messages from the Master BuildingControl Point 204 located on the same or a remote LAN or from theHierarchical Control Point located on the same LAN. This allows the MBCPto instantaneously change the opacity setting of any window in thebuilding.

It will be appreciated that what has been described above greatlyexpands the Malvino patents in terms of scalability. But the SC alsoexpands the basic functionality of the Malvino patents by providing ameans of control of SPD far beyond that envisioned in those patents. Themicroprocessor-driven device can control the modulation of the voltage,setting of any desired operating frequency and/or setting of waveformcharacteristics to at least one suspended particle device (SPD) therebycontrolling the light valve opacity characteristics of the device, aswell as a means of manually controlling the modulating means wheremanual control information is read by the microprocessor and saidmicroprocessor then adjusts modulating means based upon the setting ofthe manual control. There can be a plurality of manual control devicesand/or a plurality of individual SPDs hardwired to the microprocessordriven device. There can be a setup procedure where the relationshipbetween which one of a plurality of manual control devices is to be usedto directly control the SPD opacity of one or more of a plurality ofhardwired SPDs so as to act as if it is a single SPD. There can be ameans of externally controlling the modulating means through digitalcommands received over a communications channel. There can be a radiotransmitter and receiver, using point-to-point radio communications totransmit and receive data at neighboring microprocessor driven devices,where remote radio receiving device interprets the header of a packet ofdata sent by the transmitting device and only processes the receivingdata if necessary as determined from the packet header data. If theheader data at the receiving microprocessor specifies that said receivedata is meant for a different microprocessor driven device that is notdirectly in communication with the receiving device, the receivingdevice shall resend the data packet toward another microprocessor drivendevice or node, by consulting an on-board dynamically updated RoutingTable to send the data further along in the aforementioned network viaadditional intermediate hopping points. Once said packet of data reachesits final destination point, it is processed by application software atthat final destination.

Many different types of packets may be sent through the network, some ofwhich are used to maintain the network itself, others which movestatistical data through the network and others which move applicationdata such as Light Valve commands, through the network. One type ofnetwork packet may distribute instantaneous routing information thatwill be used at each node to assist in the determination of the bestnext route to be used to move this packet toward the destination node.Another type of packet will contain SPD Glass control command for aremote node, asking the remote node to change the local Light Valve to aparticular setting.

The system may incorporate an interface to a Local Area Network (LAN) toconnect a Master Building Control Point, a microprocessor-driven devicewhich makes intelligent decisions regarding what opaqueness should beset at an individual window, and sends commands to other parts of thesystem over the LAN. The LAN may be wired via Thinnet, Thicknet, twistedpair, optical fiber or other wired LAN means, or wireless using anyvariant of IEEE 802.11, or IEEE 802.15 or other wireless LAN means. TheLAN may be bridged to another LAN to extend restrictions on bus lengthor the number of devices connected to one bus. The LAN may be extendedusing a router in order to connect to other LANs over a much larger areaof a residential or commercial building that can be reached by a singleLAN in order to communicate with the Master Building Control Pointattached to the local or wider area network.

The controller may run a particular set of software that enables it toperform its normal functions in addition to becoming an “IntelligentControl Point” on the LAN referred to as the Hierarchical Control Point.This device is capable of communicating with every one of the devices ina hierarchy.

The system may automatically change the Light Valves under its control,based upon the physical orientation of the SPD on the earth, thelatitude and longitude of the SPD, the day of the year and the time ofthe day. The microprocessor will support a profile of data which isderived from off-line processing of the orientation of the window inspace at every moment of the year so that optimal Light Valve settingsmay continuously be made in order to reduce energy utilization inresidential and commercial environments using window based SPDs.

If manual override operations are used to override automated operations,after a specific period of time automated operations may resume.Automated operations may be resumed when a room occupancy sensor doesnot show any movement in a room for a specific period of time. Thesystem may support a small number of fixed profiles for daytime andnight time opacity settings and a switch to manually set which profileis currently in effect. There may be two profiles and the manual switchmay be labeled Summer and Winter. There may be four profiles and themanual switch is labeled Summer, Fall, Winter and Spring.

In the system, optimal Light Valve settings may be derived in real timein lieu of using a predetermined profile of information. Such real-timecalculations might be performed at the Master Building Control Point.

A device comprising the same electronics as a controller that operatesan SPD may not connected to any SPD but may only be used as anintermediate hopping point to move data between other fully SPDoperational devices, utilized in spots where radio coverage is poorwhere fully operational devices are unable to communicate directly witheach other. This hopping-point device may be placed in an otherwise deadspot between other devices, to act as a bridge between the otherdevices.

In the system, messages may flow through a hierarchy of specializednodes and not from any node to any other node in the network. At thehighest level of the hierarchy, a Control Point exists that makesintelligent decisions as to the current settings of opaqueness at allpoints in a building of SPD glass. Depending upon the size of theimplementation, there are several levels of hierarchy. One of theseBuilding Control Points communicates several lower level control pointsso that each may simultaneously act upon the command to modify the LightValve setting at a controller. The lower level control point may furtherdistribute the command to another lower level of control points tofurther spread the command to the largest number of points in thequickest time so that the windows may be activated as quickly aspossible.

In the system, messages may flow through a hierarchy of IntelligentControl Points located on the same or different LANs than the MasterControl Point. At the highest level of the hierarchy, a Control Pointexists that makes intelligent decisions as to the current settings ofopacity at all points in a building of SPD glass. Depending upon thesize of the implementation, there are several levels of hierarchy. TheMaster Control Point sends opacity modification commands to one or moreof the Hierarchical Control Points which in turn communicate withseveral lower level Hierarchical Control Points and eventually to eachof the individual controllers within its realm of control. Such amulti-level distribution of control reduces the volume of data packetstraversing the LAN on which the Master Control Point exists and handsoff the command distribution to each of the local LANs thus reducing theload on the Master and on the backbone network. It also allows forcommands to be executed more quickly than if each had to be sentdirectly from the Master Control Point, since each Hierarchical ControlPoint is performing the distribution of commands for the Master on eachof its local LANs. Therefore commands are sent simultaneously acrossmultiple LANs instead of serially. This allows a very large number ofSuspended Particle Devices to be changed more quickly andsimultaneously.

The SC may modulate the frequency across a variable range, occurringsimultaneously with the varying of Voltage driving the SPD. Driving thedevice over a variable frequency can eliminate a potential for the glassto “sing” (generating an audio tone) that would otherwise annoy humanindividuals in the same room.

A scalable controller may include a sensor circuit to detect a drop inthe current flow through the SPD. This would be indicative of a breakagein the SPD. In this event the SC sends the MBCP a “glass breakagedetection” message to denote the event. The MBCP in receiving the alarmis capable of determining which window this came from and will requesthuman intervention through any of a number of different means. Thismight include one or more radio paging messages sent over the Internet,a short message for one or more cell phones sent over the Internet,calling a central station monitoring facility and generating a syntheticvoice message, sending a message over the Internet to a monitoringservice specifically overseeing the SPD-glass building control, amongother means. The MBCP maintain hysteresis logic so that if flooded withbreakage detection messages at any one time, multiple alerts are notgenerated, unless they are not responded to in a given period of time.The MBCP is capable of turning off the glass-breakage detection logic atan SC for any period of time, so as to avoid being flooded with messagesfrom entire sections of the building, after the alert has beenacknowledged.

For all SPD applications including automotive, marine, aerospace andarchitectural, the controller of this invention can drive the SPD inmore sophisticated ways than in the Malvino patents.

First, various waveforms can be used rather than a single waveform.

Second, the duty cycle can be varied, to conserve energy.

Within the controller, two or more electro-optical lookup tables can bestored to support multiple types of SPD.

The manner of driving the SPD can be adjusted based upon externaltemperature.

And, power can be dynamically managed to optimize power consumption.

The Malvino U.S. Pat. Nos. 6,897,997 and 6,804,040 provided for a basicmethod of driving SPD based material so that it changes from its clearto dark state or to various levels of opacity in between. These basicpatents do not address the full operational parameters of SPD or theircontrol. The microprocessor-centric SC provides for an unprecedentedlevel of fine and optimized control of SPD through severalmethodologies, algorithms and feedback mechanisms that this enhancedcontroller patent describes.

The Malvino '997 and '040 patents were concerned with the creation ofsome set of electronics that would allow SPD-based material to changestate. But detailed studies of the nature of SPD reveals that there areseveral features of SPD other than opacity that must be taken intoaccount to properly control SPD-based windows. And there are manyvariable factors which control these features.

The main feature of SPD is in its ability to move from a clear state toa dark state and back again or to any intermediate opacity level, basedupon the frequency and AC voltage level applied. But other importantfeatures to control are switching time, haze, clarity, possible singingor humming of the SPD laminated between two pieces of glass or plastic,and power consumption. There are many parameters whose settings affectthese features. These are AC voltage, frequency, frequency tolerance,temperature, wave form, wave phase, duty cycle, thickness of the SPD,the manufacturer of the SPD and sometimes which production run itselfwithin one manufacturer. The simple circuits of the Malvino U.S. Pat.Nos. 6,897,997 and 6,804,040 are incapable of factoring in all of theseparameters to provide the desired performance of the SPD.

Different applications of SPD will require optimization of some mannerof operating a SC. In building applications that are targeted at energyefficiency the SC will emphasize those functions aimed at energyconservation. Switching speed would be traded off for energy efficiency.In an automobile the vendor may wish opacity changing time, alsoreferred to as glass switching time or glass switching speed, to remainconstant regardless of the exterior temperature of the vehicle. The SCcan insure a lower switching speed by driving the SPDs at a higherfrequency when the outdoor temperature is very low at the expense ofutilizing more power.

FIG. 24 shows the logical structure of an embodiment of the invention.This is an enhanced controller not only in its ability to become part ofa larger coordinated network of controllers, but it the enhancedintelligence of each individual node in its control of SPD.

The Command and Control portion of the controller receives commands froman external source (such as an optional A/D type device like a dimmerswitch for example) or other microprocessors over a communications link,to set the light opacity level of SPD Glass to a particular level. TheSC may utilize sensors through its A/D interface to determine theexternal temperature to take this into account to optimize eitherswitching time or power consumption, whichever is of more importance tothe user. A particular shape wave form is set up by the wave generationlogic which modulates the required amount of power at the optimalfrequency to switch the glass. To reduce the power being utilized tomaintain the SPD at a particular opacity level, the duty cycle of thewaveform utilized is reduced. Algorithms built into the software of theSC take into account the goal which is to be achieved and adjust thesetting of the factors mentioned to provide the desired goal. The SC hasfull flexibility to adjust all performance affecting parameters in aparticular environment.

The controller has a series of internal 3-dimensional tables similar toFIG. 25, which map various operational parameters against others inorder to know how the changing of one factor or two factors will affectthe third. For example, the table might define the proper voltage andfrequency required for absolute levels of light transmission. Anothersuch table would describe the relationship between switching time andfrequency for a given amount of power. A third table would provide amodel of switching time and frequency for a given temperature. A fourthtable would evaluate switching time and frequency for a giventemperature.

Using algorithms built into the intelligent controller it may maketrade-offs to optimally operate SPD according to the goals that areprogrammed into its memory. If the maintenance of switching time at lessthan 2 seconds from dark to clear is desired, then these algorithms willpull data from these tables to increase the frequency of the AC signal,increase the voltage and provide extra power in order to provide aspecific level of opacity for a particular manufacturer's SPD. If inanother instance, power consumption was the factor for optimization, theSC would operate the SPD at a lower frequency and adjust the voltageaccordingly in order to achieve absolute levels of opacity, where thereduced power consumption would be at the expense of a switching speedof perhaps 8 seconds instead of 2.

This data is repeated for each manufacturer of SPDs so that thecontroller may make proper decisions based upon the particular SPD beingutilized. There may be a day when industry standardization will insurethat all SPD reacts in exactly the same repeatable way acrossmanufacturers and across production runs from one manufacture, but untilthe industry can achieve this level of quality control across differentmanufacturing processes, multiple tables which model performance must bepreprogrammed into the tables of the controller. But the end result isthat the controller is a universal controller for all SPD applications.

The set of tables stored in the controller are typically createdoff-line through laboratory experimentation of each manufacturer's SPD.The resultant data is stored in the tables of the controller or may bedownloaded into the controller over its communication channel.

In some implementations of the controller some of the three-dimensionaltables will be collapsed to two dimensions as the third factor is notone measured or under the control of the particular model of controller.For example, a basic model of controller may not utilize a temperaturesensor and will operate continually under the assumption of a fixedoperating temperature. One of the sets of tables in the controller isknown as the EO (Electro-Optical) table. This table is ordered byopacity at 0% (dark) to 100% (clear). Each entry contains the optimalfrequency and voltage to set a particular manufacturer's glass to thegiven opacity level. If temperature is not going to be considered in theoperation of this version of the controller, the EO table remainstwo-dimensional.

In addition to using its algorithms and internal tables to set thevarious parameters to control the SPD, the controller can dynamicallychange its parameter settings based upon measurement and feedback fromsensors connected to its A/D inputs. For example, a light source andphotocell or phototransistor or other photodetector may be used to shinea specific intensity light through the changing SPD and to a photocellwhich will detect the actual light level. The EO table being used toswitch the SPD to a particular opacity level may not have a temperaturecomponent in its entry. But the controller can measure actual switchingtime by measuring how long it takes for the glass to reach the opacitylevel requested, because its light/photocell logic can measure when theactual opacity level has been achieved. Knowing the time, the controlleralgorithms can determine a better frequency and voltage to operate theglass to reduce the switching time to the desired level. The measuringdevices are used in the creation of a feedback loop to auto-adjustoperational parameters.

The intelligent controller is able to further reduce the amount of powerconsumption of SPD to values lower than that achieved by operating theSPD at an optimal frequency and voltage for a given opacity level at agiven temperature. The controller may change the duty cycle of the poweroutput to not keep the SPD under constant AC power. Logic in thecontroller can reduce the number of complete wave form cycles beinggenerated over a given period of time. So if ‘m’ cycles would normallyoccur in time T, every other cycle could be ignored and power shut downin those cycles, to achieve a 50% duty factor. In general the goal is toonly keep the power operating only ‘n’ out of every ‘m’ cycles in orderto reduce power. At some point there will be a visible flickering of theSPD noticed. Experimentation derives another three-dimensional tablewhich specifies the lowest allowable duty cycle for a given opacitylevel against a third parameter such as operating temperature.

Experimentation and an analysis of the three-dimensional graphs ofoperational parameters and their resulting features, reveal other mixedoperating modes by taking advantage of aspects of different graphs.Reasonable switching speeds of 2 seconds dark to clear at roomtemperature can be achieved at 60 Hz and 20-100 volts AC. More optimalenergy performance is achieved below 60 Hz, perhaps better at 30 Hz,without causing flickering in the SPD. Higher frequencies (400 Hz) canswitch the SPD much faster but use more power to effect the switching.The controller takes advantage of these factors when optimizing forswitching speed by shifting to a higher frequency during the transitionfrom one opacity level to another then reducing the frequency to thelower allowable range to maintain the opacity setting at low power.

It will be appreciated that one skilled in the relevant art may readilydevise myriad obvious variants and improvements upon the inventionwithout undue experimentation, none of which depart in any way from theinvention and all of which are intended to be encompassed within theclaims which follow.

The invention claimed is:
 1. A controller controlling the opacity of atleast one SPD, wherein a fixed intensity light source and photo-detectorcombination is used to determine the absolute opacity of the at leastone SPD.
 2. The controller of claim 1 wherein the controller utilizesthe fixed intensity light source and photo-detector combination toprecisely set the opacity of the at least one SPD.
 3. The controller ofclaim 2 wherein the setting of the opacity to a specific level occurswithin a specific period of time.
 4. A method for use with a controllercontrolling the opacity of at least one SPD and with respect to thesetting of the at least one SPD to a specific opacity, the controllercomprising a fixed intensity light source and photo-detector combinationto determine the absolute opacity of the at least one SPD, the methodcomprising the steps of: determining the opacity of the at least one SPDby utilizing the photo-detector to measure the amount of light passingthrough the SPD.
 5. The method of claim 4 in which operationalparameters that drive the at least one SPD to be set to a specificopacity are derived from the fixed intensity light source andphoto-detector combination.
 6. The method of claim 4 wherein the settingof the opacity to a specific level occurs within a specified period oftime.
 7. A method for use with a controller controlling the opacity ofat least one SPD, the method comprising the steps of: determining thephysical location of the orb of the sun in the sky; determining from thephysical location, a relative intensity of the sunlight hitting the atleast one SPD and the controller utilizing the relative intensity of thesunlight hitting the at least one SPD to adjust the opacity of the atleast one SPD to allow or block the sunlight from passing through the atleast one SPD.
 8. The method of claim 7 in which the controller can readthe day of the year from an external source or through manual means, thecontroller further able to determine its location through aninterconnected GPS, through an algorithm or through manual means, themethod utilizing the physical location of the orb of the sun todetermine the angle at which sunlight is hitting the at least one SPDand further using the day of the year and current location to determinethe season of the year at the current location and to adjust the opacityof the at least one SPD to allow or block sunlight from passing throughthe at least one SPD in order to reduce heat passing through the SPD inhot seasons and allow heat to pass through the SPD in cold seasons.
 9. Asystem for use with at least one SPD, the at least one SPD having avariable opacity, the system comprising: a controller connected to theat least one SPD and controlling the opacity of the at least one SPD;wherein the controller automatically changes the opacity of its SPDbased upon the physical orientation of the SPD device on the earth, thelatitude and longitude of the SPD device, the day of the year and thetime of the day.
 10. A system for use with at least one SPD, the SPDhaving a variable opacity, the system comprising: at least onecontroller connected to the at least one SPD and comprising meanscontrolling the opacity of the at least one SPD; the at least onecontroller further comprising a network interface which iscommunicatively coupled to a multiplicity of controllers having networkinterfaces; wherein at least one of the multiplicity of controllers isconnected to at least one sensor from which sensor data is read; thesensor data being used to lookup a lookup table of specific opacity towhich to set the at least one SPD and the at least one controller toutilize the looked up data to set the opacity of the at least one SPD tothat specific opacity.
 11. The system of claim 10 in which the sensordetects sun light level and the looked up data associates sunlight levelwith opacity levels.
 12. The system of claim 10 in which the sensordetects occupancy of a room and the looked up data determines theopacity when occupancy is detected or occupancy in not detected.
 13. Thesystem of claim 10 wherein the at least one sensor is a means fordetecting an audio frequency associated with glass breakage and thelooked up data is means for determining the setting of the opacity ifthe audio frequency associated with glass breakage is detected.
 14. Thesystem of claim 10 in which the sensor detects indoor temperature of aroom and the lookup table determines the setting of the opacity giventhe detected indoor temperature.
 15. The system of claim 10 in which thesensor detects outdoor temperature and the lookup table determines thesetting of the opacity given the detected outdoor temperature.
 16. Thesystem of claim 10 having a multiplicity of SPDs and a multiplicity ofsensors each detecting geographic orientation data of SPDs on abuilding, the geographic orientation data used by the at least onecontroller to modify the opacity of each SPD from that of SPDs at otherorientations.
 17. The system of claim 10 in which the sensor detectselectrical current and the lookup table determines the setting of theopacity given the detected electrical current.
 18. The system of claim10 in which the sensor detects electrical voltage and the lookup tabledetermines the setting of the opacity given the detected electricalvoltage.
 19. A system for use with at least one SPD, the SPD having avariable opacity, the system comprising: at least one controllerconnected to the at least one SPD and comprising means controlling theopacity of the at least one SPD; the at least one controller furthercomprising a network interface which is communicatively coupled to amultiplicity of controllers having network interfaces; wherein acrossthe multiplicity of controllers there exists at least two connectedsensors from which sensor data is read; the sensor data of at least oneconnected sensor containing geographic location information, the sensordata being used with a first lookup table specifying a secondary lookuptable based upon the sensor data, the sensor data of the second sensorof the at least two connected sensors being of a non-geographic sensingtype, the non-geographic sensor data being used with a secondary lookuptable to lookup a specific opacity to which to set the at least one SPDbased upon the non-geographic sensor data and the at least onecontroller to utilize the looked up data from the secondary lookup tableto set the opacity of the at least one SPD to that specific opacity.